The subject matter disclosed herein relates to fuel nozzles and, more specifically, to flow adjustment orifice systems for fuel nozzles.
Gas turbines can utilize fuel nozzles to direct the flow of air and/or fuel for combustion. Exemplary air and/or fuel combustion components can include compressed air, gas, oil and other combustible fuels. These air and/or fuel combustion components may be directed from their original source, through the fuel nozzle, and into a combustion area where the air and/or fuel is ultimately combusted. This combustion may then drive the rotation of the gas turbine during its operation.
When the air and/or fuel is directed through the fuel nozzle, it may pass through one or more orifices, channels, segments and/or other types of pathways. Thus, the dimensions of these pathways, such as the open cross-sectional area for an air/fuel inlet orifice, may assist in controlling the amount of air and/or fuel that passes through the fuel nozzle for combustion. However, these various pathways may wear over time due to, for example, the air/fuel itself passing there through, the overall operating conditions of the fuel nozzle, or various other elemental conditions such as foreign particulates or abrasions. The wearing of the pathways may in turn affect the amount of air and/or fuel passing through the fuel nozzle and potentially result in a non-uniform or excessive combustion. For example, when an air/fuel inlet orifice becomes worn, it may have a greater open cross-sectional area than originally designed and result in an excess of air/fuel passing through the fuel nozzle for combustion. While additional material may be added to worn fuel nozzles (e.g., via welding) to return the worn fuel nozzles to their original size and shape, such processes may be labor intensive and difficult to accomplish with consistent precision.
Accordingly, alternative flow adjustment orifice systems for fuel nozzles and metered fuel nozzles incorporating the same would be welcome in the art.